Systematics

Psarocolius montezuma is monotypic.

Described as Cacicus Montezuma Lesson 1830; type locality "Mexico"

This species is a member of a group of oropendolas that formerly often were separated in the genus Gymnostinops (e.g., Hellmayr 1937, Meyer de Schauensee 1966, Sibley and Monroe 1990), distinguished from other oropendolas by the presence of a patch of bare skin at the base of the bill; other species in this group are P. guatimozinus (Black Oropendola); P. cassini (Baudo Oropendola); and P. bifasciatus (Olive Oropendola). Phylogenetic analysis of DNA sequence data, from both mitochondrial and nuclear genes, reveals that the species of "Gymnostinops" are embedded within Psarocolius, and are sister to Psarocolius decumanus (Crested Oropendola) (Price and Lanyon 2002a, 2002b, 2004, Powell et al. 2014).

Many aspects of song are conserved across Psarocolius. A comparison of song structure and oropendola phylogeny, however, reveals rapid divergence of songs of P. montezuma, presumably due to a recent influence of sexual selection (Price and Lanyon 2002a).